Reagent-free intramolecular hydrofunctionalization: a regioselective 6-<i>endo-dig</i> cyclization of <i>o</i>-alkynoylphenols
作者:Chanhyun Jung、Siyuan Li、Kwanghee Lee、Mayavan Viji、Heesoon Lee、Soonsil Hyun、Kiho Lee、Young Kee Kang、Chhabi Lal Chaudhary、Jae-Kyung Jung
DOI:10.1039/d1gc04848a
日期:——
Solvent-directed intramolecular hydrofunctionalization of readily available o-alkynoylphenols 1 was successfully achieved under reagent-free conditions. The hydrofunctionalization of 1 occurred by nucleophilic attack on the phenolic oxygen followed by consecutive migration of the phenolic H atom to the alkyne center, eventually affording γ-benzopyranones 2. The phenol O–H group forms intramolecular H-bonds
在无试剂条件下成功实现了容易获得的邻炔基酚1的溶剂导向分子内氢官能化。1的氢官能化通过对酚氧的亲核攻击随后酚氢原子连续迁移到炔烃中心而发生,最终得到 γ-苯并吡喃酮2。酚 O-H 基团与羰基形成分子内 H 键,我们预测这些 H 键在极性溶剂存在下可以扭曲成它们最优选的构象。区域选择性 6 -endo-dig环化似乎在热力学上优于 5 -exo-dig循环化,由 DFT 计算支持。该策略之所以引人注目,是因为它无试剂、区域选择性、原子经济性高、原子、碳和反应质量效率高。